In rocket flight, forces become balanced and unbalanced all the time. A rocket on the launch pad is balanced. The surface of the pad pushes the rocket up while gravity tries to pull it down. As the engines are ignited, the thrust from the rocket unbalances the forces, and the rocket travels upward.

What causes the rocket to fly?

Rockets work by a scientific rule called Newton's third law of motion. ... The exhaust pushes the rocket, too. The rocket pushes the exhaust backward. The exhaust makes the rocket move forward.

How do rockets fly in space?

In a similar manner, a rocket moves in space because the gases are given momentum as they are expelled by the rocket engine. ... This momentum change of the gases gives the rocket the "push" to go forward. We call this push, the thrust of the rocket, i.e. the force exerted on the rocket.